Given the product and application, either will do fine. If it makes you feel any different, go with the cheaper one or the more expensive one if you have a preference on being frugal or extravagant.

In the application of thermal paste, less is truly more, since the purpose to merely to maximize thermal transfer by eliminating any air pockets between the chip's surface and the thermal panel/heat sink that comes into contact, rather than using more of the paste in an effort to improve heat transfer.

You need very little. For desktop processors, a blob the size of a grain of rice is about right. Since this is a mobile chipset and there's probably no big IHS on top, you'll likely need much less. You want the thinnest possible layer that covers the entire area.

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